Republicans' claims are far more likely than Democrats' to be rated false by the fact-checking site PolitiFact, according to a study released Tuesday.

Since January, PolitiFact has rated 52 percent of Republicans' statements as mostly or entirely false, compared to just 24 percent of Democrats' statements, the study found. In the first three weeks of May, amid controversies over the attacks in Benghazi, Libya and investigations at the Internal Revenue Service and the Department Of Justice, 60 percent of Republicans' statements were rated as false, compared to 29 percent of those made by Democrats.

George Mason University's Center for Media and Public Affairs, which conducted the study, looked at 100 claims, 46 made by Democrats and 54 by Republicans.

Rep. Michele Bachmann's (R-Minn.) claim that the IRS runs a "huge national database" of personal details, for instance, got a "pants on fire" rating.

“While Republicans see a credibility gap in the Obama administration, PolitiFact rates Republicans as the less credible party,” George Mason University CMPA president Robert Lichter wrote in a release with the Tuesday report.

The center released similar findings last year when it compared the Obama and Romney campaigns, giving Obama higher marks on truthfulness.

The study is far from a scientific referendum on partisan honesty -- as PolitiFact's editor Bill Adair noted, the statements it chooses to check aren't a representative sample of what either party is saying.

"PolitiFact rates the factual accuracy of specific claims; we do not seek to measure which party tells more falsehoods," he told Beaujon. “The authors of this press release seem to have counted up a small number of our Truth-O-Meter ratings over a few months, and then drew their own conclusions.”

Then-Sen. John Ensign (R-Nev.) was a proponent of the Federal Marriage Amendment, which would have banned states from recognizing same-sex marriage. "Marriage is the cornerstone on which our society was founded," he argued on the Senate floor in 2004. He also called on President Bill Clinton to resign over the Monica Lewinsky scandal, <a href="https://www.huffpost.com/entry/ensign-whacked-clinton-fo_n_216508">saying it had destroyed the president's credibility</a>. Yet in 2009, Ensign admitted that he had had an extramarital affair with a former campaign staffer who was also the wife of one of his top aides. An ethics investigation by the Senate Ethics Committee and the FBI followed, and<a href="https://www.huffpost.com/entry/john-ensign-resigns-reports_n_852285"> Ensign resigned</a> in 2011.